equivalent syntax for 'for loop' & 'while loop'? - php

Question

I know basic examples about foreach to for loop and while loop since I was begin coding I didn't paying attention from the speed of executing a script which it is very very important since then I keep converting all my for each statement to for loop. If it's comes to array i'm quite confused -_-. I know it gives me down vote posting this. LIKE I'd rather let people figure things out for myself.
I just need a bit of guide using a for loop statement. How can I convert the following foreach loop to for loop/ while loop statement?
like what I seen on phpbenchmark.com as
$i = 0; while($i < 1000000) ++$i;
for($i = 0; $i < 1000000; ++$i);
CODE:
<?php
$user['001'] = 'A';
$user['002'] = 'B';
$user['003'] = 'C';
$user['004'] = 'D';
foreach($user as $id => $name)
{
echo '<br>Id='.$id.'Name='.$name;
}
?>
thanks alot.
EXPECTED OUTPUT LIKE foreach output:
Id=001Name=A
Id=002Name=B
Id=003Name=C
Id=004Name=D
also what if I have an array keys like
$user['AAA'] = 'A';
$user['BBB'] = 'B';
$user['CCC'] = 'C';
$user['DDD'] = 'D';
it will output as:
Id=AAAName=A
Id=AAAName=B
Id=AAAName=C
Id=AAAName=D

Answer 1

The for and while loops you show are simply incrementing a number, which you can use to access elements of an array if the keys of that array are equivalent to those numbers. In other words, for or while loops have nothing to do with arrays as such, you're just using a number as a key to an array.
If your array keys are not simple continuous integers, this is more problematic. You could try to construct the correct keys from your $i variable, but why? You should just iterate explicitly over the keys of the array, for which foreach is perfect. You can also do it with each or any number of other complicated ways:
while (list($key, $value) = each($array)) {
...
}
But I doubt it's going to be significantly faster than a foreach.

Answer 2

Something like this...
<?php
$user['001'] = 'A';
$user['002'] = 'B';
$user['003'] = 'C';
$user['004'] = 'D';
while (current($user)) {
echo '<br>Id='.key($user).'Name='.$user[key($user)];
next($user);
}

Answer 3

try this
$user['001'] = 'A';
$user['002'] = 'B';
$user['003'] = 'C';
$user['004'] = 'D';
$keys = array_keys($user);
$length = sizeof($user);
for($i=0; $i<$length; $i++) {
echo 'id: '.$keys[$i].' value: '.$user[$keys[$i]].'<br />';
}

Answer 4

do you wanted something like this?
$length = count($user);
for ($i = 0; $i < $length; $i++) {
print $user[$i];
}
EDIT: or something like this?
$user = array ( '001' => 'A',
'002' => 'B',
'033' => 'C' );
while( list ( $id, $name) = each ( $user) )
{
echo '<br>Id=' .$id. 'Name='.$name;
}
EDIT:also works with you r AAA = A etc case